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The coalfield in the northwest suburbs of Xuzhou has suffered from extensive land subsidence; however, the temporal nonlinearity and corresponding spatial variation of its surface deformation has not been adequately explored. This study revealed complex surface deformation of the study area from 2015 to 2020 using time series InSAR. A general trend from sharp subsidence to moderated subsidence or even uplift is observed. Three main characteristic types of deformation time series, namely “Subsidence (S)”, “Subsidence–Uplift (S-U)” and “Subsidence–Uplift–Subsidence (S-U-S)”, were detected. Generally, mining activities control the fundamental constraining factors for the surface deformation. Mine closures affect the date of reversal from subsidence to uplift, or in other places the return to subsidence after uplift. Higher deformation rates in preceding sections of the deformation time series are generally correlated with later reversals of deformation trend and higher deformation rates of the succeeding sections of the time series. However, universally applicable spatial and temporal patterns of deformation were not detected, suggesting that surface deformation in the study area is a very complex process. Detailed process and mechanism analysis of surface deformation in the study area should focus on specific mines and pay particular attentions on dewatering and subsequent flooding of mines.

The purpose of this study is to investigate the potential mitigation strategies to overcome the overheating issue at the attic of the landed residential house located in a hot and humid climate area. An existing terrace house with 178 m2 was selected for this research. A building simulation model was created and calibrated by using the previous site measurement data collected by Ng et.al. in the year 2018. The calibrated model was subsequently used to evaluate various retrofitting methods and strategies, including roof insulation, and passive radiative cooling methods. The study shows that high albedo cool roof paint is the most effective roof retrofitting strategy compared to other approaches.

The poor gradation of manufactured sand limits the application in concrete work. Hence, in order to study the influence of the gradation of manufactured sand on the performance of mortar, this paper removes the stone powder from the manufactured sand, increases the content of different sands based on the mid-value of gradation, mixes it with different proportions of stone powder and tests the expansion degree of mortar with the water-binder ratio of 0.35, 0.4 and 0.45 respectively. The test results show that the influence of the gradation of manufactured sand on the expansion degree of mortar depends on the stone powder content and water-binder ratio. When the stone powder content is less than 5%, the expansion degree of motor will be reduced with the gradation adjustment; if the stone powder content is more than 5%, the expansion degree of mortar will show different characteristics with the gradation adjustment under different water-binder conditions.

A large amount of volatile organic compounds (VOCs) produced by industry have caused serious environmental pollution. In this paper, the removal effect of simulated xylene by strong ionization dielectric barrier discharge (DBD) plasma at atmospheric pressure and its degradation mechanism and pathway were studied. The effect of gas residence time, and initial xylene concentration was studied. The results showed that higher voltage caused an increase in discharge power, and with the increase of voltage, the concentration of ozone and nitrogen oxide in the reactor increased. The degradation efficiency decreased from 98.1% to 80.2% when xylene concentration increased from 50 ppm to 550 ppm at 4kV. And with the increase of residence time from 0.301s to 1s, the degradation efficiency increased from 78.5% to 98.6%. According to GC-MS analysis, the degradation products were ethyl acetate and n-hexylmethylamine at 4kv. And the main intermediates are 2,4-2-tert-butylphenol, 2-aminopentane, 2-methyl-5 - (2-aminopropyl) - phenol and propionamide at 1.5kV.

In the process of globalization, the integration of world tourism is becoming more and more obvious. With the rapid development of China’s tourism industry, Tourism in many provinces and cities has become a pillar industry or key industry, The various risks it faces are also gradually highlighted. Driven by regional economy, the capitalization operation of national culture is considered to be an effective way to protect national culture and develop economy in ethnic areas. However, national culture has brought many social problems in the process of concrete operation. This paper discusses the realistic dilemma of cultural capitalization in the tourism development of Miao villages in Xijiang, This paper points out that only by clarifying the relationship between the stakeholders in the operation of cultural capital and further clarifying the marketing strategy of cultural capital operation can we ensure the sustainable development of national culture capitalization.

The main structure of the multifunctional loading and unloading machine is analyzed and designed, including feeding conveyor, intermediate conveyor and unloading conveyor. According to the action of each part of the hydraulic system and electrical system design, in order to meet the needs of more working conditions, the working mechanism realized the overall slip, telescopic conveyor lifting, rotating, telescopic; Combined with the convenience of worker operation, three control modes of remote control, workbench control and terminal control are designed.

The occurrence of local or regional major public health emergencies has seriously damaged human health and life safety, and has an impact on the psychological state of the public. The study introduces “social amplification of risk” effect and the mechanism of emotional infection, and constructs a process model of psychological prediction, psychological cognition and psychological behavior in the generation of social psychology of major public health emergencies, and from the level of individual emotions, group emotions and social emotions analyze the evolutionary model of social psychology; Research has found that information disclosure, government trust and social confidence are the main factors influencing the formation of social psychology of major public health emergencies.

The underground pipeline of campus is an extremely complex and huge system, and the traditional pipeline management mode can no longer meet the requirements of campus development and planning. The 3D geographic information visualization method can accurately describe the location and distribution information of various pipelines and spatial features, which can better serve the management of underground pipelines on campus. This paper designed overall framework and technology framework of underground pipeline information system, the system is satisfied with the PC, Web, mobile terminal and other multi-client access. In this paper, the key technology points of underground pipeline system construction on campus are comprehensively analyzed, and the feasibility of the technology is verified by combining with the practical application of underground pipeline system in lanzhou university.

On the basis of the analysis and summary of several maritime transport support modes for the material replenishment of islands and reef, a DEA model is established in this study to calculate the relative validity of the above-mentioned modes by solving the linear programming question. Consequently, the support modes can be sorted by the validity value. Finally, impact factors can be located and improvements can be made through eliminating the variables, leading to potential room for maritime transport support optimization.

Addition of fiber to dental bridgework was thought to be more efficient comparing to porcelain-fused to metalwork. In other side, some patients consumed alcoholic beverage in their daily life. This study aimed to determine mechanical properties of fiber-reinforced composite (FRC) exposed to alcoholic beverage. The materials used were dental resin (i-FLOW i-dental, Lithuania), polyethylene fiber (Vactrise, USA), and 4 alcoholic beverages. FRC samples (40) were divided into 10 groups (n=4, control:aquades). Each Sample was soaked in beverage for 5 s followed by 5 s in aquades for each cycle (10 cycles daily for 4 wk). Mechanical properties were examined for hardness and flexural strength. The result showed the mean values for hardness (KHN) were: 98.70±6.03 (aquades), 99.01±4.92 (Beer), 87.65±7.83 (Vermouth), 80.23±5.22 (Rum), 78.20±3.70 (Tequila); while for flexural strength (MPa) were: 336.00±25.05 (aquades), 308.25±10.39 (Beer), 215.07±34.86 (Vermouth), 194.89±27.69 (Rum), 175.48±33.58 (Tequila). The ANOVA revealed significant differences in hardness and flexural strength (p

The type of lines which from digital hand drawing representation is the central element to the constituted form. At present, there are a few special topics on the structural description of the type of lines. According to the classification of kind of lines which from the basis of painting, integrated using of various lines can create spatial illusions in the plane horizon to achieve the performance of three-dimensional entities. By clarifying features and characteristics of various lines, the digital technology can be quickly generated to design the representation effect and form the graphic design language.

This paper discribes the spatial thinking ability, materials processing, design easthetics application and technical implementation are four aspects that very important to cultivate students– professional quality when building a manual model. It stresses the handwork l model course has played positive significance in the aspect of design basic teaching under the background of High-Tech.

CO2 injection to strengthen shale gas development is a new technology to improve shale gas recovery and realize geologic sequestration. Many scholars have studied these aspects of this technology: mechanism of CO2 displacement CH4, CO2 and CH4 adsorption capacity, affecting factors of shale adsorption CO2, CO2 displacement numerical simulation, and supercritical CO2 flooding CH4 advantages. Research shows that CO2 can exchange CH4 in shale formations, improve shale gas recovery, on the other hand shale formations is suitable for CO2 sequestration because shale gas reservoir is compact. The supercritical CO2 has advantages such as large fluid diffusion coefficient, CO2 dissolution in water to form carbonic acid that can effectively improve the formation pore permeability etc., so the displacement efficiency of supercritical CO2 is high. But at present the technology study mainly focus on laboratory and numerical simulation, there is still a big gap to industrial application, need to study combined effect of influence factors, suitable CO2 injection parameter in different shale gas reservoir, CO2 injection risk and solutions etc.

With the development of industrial automation, location measurement of 3D objects is becoming more and more important, especially as it can provide necessary positional parameters for the manipulator to grasp the object accurately. In view of the disabled object which is in widespread use currently, its image is captured to obtain positional parameters and transmitted to manipulators in industry. The above process is delayed, affecting the work efficiency of the manipulator. A method for calculating the position information of target object in motion is proposed. This method uses monocular vision technology to track 3D moving objects，then uses contour sorting method to extract the minimum constrained contour rectangle, and combines the video alignment technology to realize the tracking. Thus, the measurement error is reduced. The experimental results and analysis show that the adopted measurement method is effective.

Nitrous oxide (N2O) is a common greenhouse gas and urgent need to be contained. Direct catalytic decomposition of N2O by high activity catalyst into N2 and O2 is a low-cost and harmless method. Bimetallic catalysts show good catalytic activity in many classes of reactions, and plasma technologies, applied to prepare of catalyst, are considered to be a promising method. In our contribution, DBD cold plasma is applied to synthesize Rhodium and Cobalt bimetallic catalysts for catalytic N2O decomposition. The influence of cobalt and rhodium content on N2O decomposition activity shows that the optimal amount of metal is determined as 5wt. % cobalt and 0.5wt. % rhodium loaded on Al2O3. The best working voltage is determined as 18kV. The results indicated that the Rh/Al2O3 catalysts prepared by atmospheric-pressure DBD cold plasma showed smaller size and high dispersion of Rh particles, so that the metal-support interaction and the catalytic activity are enhanced. Atmospheric-pressure DBD cold plasma is proved to be an environmentally friendly and efficient method for preparing high performance Rhodium and Cobalt bimetallic catalysts for catalytic N2O decomposition.

Pull-push ventilation system, with high capture efficiency, is universally used to capture contaminants from containment generation where can’t be enclosed and where the working area is large. When there are obstacles between the pull hood and the push hood, the air jet will disperse, leaving contaminants out of control, causing atmosphere polluted. This paper aims to discuss flow filed of pull-push ventilation system, located in some tank of some plating workshop, with obstacles between pull hood and push hood. Mathematical model, involving physical model, assumptions, governing equations, boundary conditions and grid separation is established. By CFD code FLUENT, flow field, containing velocity field and concentration field, is achieved. To verify the simulation models, velocity field for simulation results is compared with the theory results, while concentration field for simulation results with experimental results. The comparison results show that the results matches well and that mathematical model proposed in this paper is reasonable, helpful and realistic significant in designing this kind exhaust ventilation systems where obstacles presence.